The group said governments in countries like Egypt have to build democracy while ensuring the rights of minorities, women and other groups are not trampled.
"The uncertainties of freedom are no reason to revert to the enforced predictability of authoritarian rule," Executive Director Kenneth Roth said. "The path ahead may be treacherous, but the alternative is to consign entire countries to a grim future of oppression."
Human Rights Watch's 665-page report, World Report 2013, reviews 90 countries around the globe.
In the countries affected by the Arab Spring, leaders have a daunting task, the group said. They must build effective political institutions, independent courts and professional police agencies.